Eur. J. Entomol. 111(5): 663–668, 2014 doi: 10.14411/eje.2014.080 ISSN 1210-5759 (print), 1802-8829 (online) Dispersal of individuals of the flightless grassland ground beetle, Carabus hungaricus (Coleoptera: Carabidae), in three populations and what they tell us about mobility estimates based on mark-recapture ZOLTAN ElEK 1, Lukáš DRag 2, 3, PAVEL POKLUDA2, 3, *, Lukáš ČížEK 2, 3 and SÁNDOR BéRCEs 4 1 MTa-ElTE-MTM Ecology Research group, Hungarian academy of sciences, c/o Biological Institute of Eötvös loránd University, Pázmány Péter sétány 1/C., H-1117 Budapest, and Hungarian Natural History Museum, Baross u. 13., H-1088 Budapest, Hungary; e-mail: [email protected] 2 Faculty of science, University of south Bohemia, Ceske Budejovice, Czech Republic 3 Institute of Entomology, Biology Centre, academy of sciences of the Czech Republic, Branisovska 31, 370 05 Ceske Budejovice, Czech Republic; e-mails: [email protected]; [email protected] 4 Duna-Ipoly National Park Directorate, Budapest, Hungary, e-mail: [email protected] Key words. Coleoptera, Carabidae, Carabus hungaricus, dispersal, inverse power function, Hungary, Czech Republic, Natura 2000 Abstract. Knowledge of the dispersal ability of endangered species is crucial for developing effective, evidence-based conservation policies. Due to their limited dispersal abilities and specific habitat requirements, insects are among the animals most threatened by habitat fragmentation. We studied three populations of the highly endangered species of ground beetle, Carabus hungaricus, at three sites in Central Europe (Hungary and Czech Republic) using mark-release-recapture (MRR). The total catch of 574 pitfall traps set at the three sites was 6255 individuals. Depending on the site, the percentage recaptured was 13–32%. average and maximum distance moved by individuals of both sexes at each of the sites ranged between 47–132 and 207–1104 m, respectively. The probability of the movements following an inverse power function (IPF) for the two sexes did not differ, but did differ among sites. Probability of dispers- ing for distances >100 m differed by an order of magnitude between sites, most likely because of differences in how the samples were collected. Despite the fact that individual beetles are able to move over distances in the order of kilometres, the high fragmentation of their habitats is likely to prevent them from colonizing most uninhabited habitat patches. Therefore, the conservation of this threatened ground beetle could be improved by adopting and implementing a policy of assisted dispersal. Our results from three study sites also provide an interesting illustration of the variability in the estimates of the probability of dispersal obtained using MRR. INTRODUCTION ing on spontaneous colonisation in restoration programmes Animal dispersal is a crucial biological trait that allows (e.g. Schultz, 1998; Maes et al., 2004). individuals to colonise new habitats, locate mating part- Mark-release-recapture (MRR) data and regression mod- ners, food and other resources (Clobert et al., 2004; Bowler els based on them are among the most common tools used & Benton, 2005). Due to combination of their limited dis- to estimate animal dispersal (e.g. Hill et al., 1996; Fric & persal abilities and specific habitat requirements, insects Konvicka, 2007; Zimmermann et al., 2011). Compared to are among the animals most threatened by habitat frag- other methods, such as population genetic analyses, telem- mentation (Ewers & Didham, 2005). Increasing interest in etry, and dispersal simulators (i.e. flight-mills), the MRR- biodiversity conservation, i.e. safeguarding occurrence of based results tend to give lowest dispersal estimates due species in a fragmented landscape (e.g. Petit et al., 2001) to underestimation of long-distance movements (Koenig requires also knowledge on their dispersal abilities. Im- et al., 1996; Jonsell et al., 2003; Drag et al., 2011; Chiari proved analytical tools allow to study the dispersal of vari- et al., 2013; David et al., 2013; Oleksa et al., 2013), and ous model organisms (Petit et al., 2001; Ulrich & Zalewski, vary due to local conditions and/or sampling designs (e.g. 2007) in different landscapes (Van Dyck & Baguette, 2005; Stevens et al., 2010; Hassal & Thompson, 2012). However Bonte et al., 2006; Sander et al., 2006; Campagne et al., little is known how MRR-based estimates of a species mo- 2009). Despite the advances, the questions most frequently bility vary due to local conditions or sampling designs for asked by conservationists remain simple: what is the prob- ground beetles as one of the important model groups in ability for an average individual to cross a given distance, terrestrial ecology (Thiele, 1977). and what is the range of maximum distances that individu- The ground beetle Carabus (Pachystus) hungaricus hun- als from a given population may realistically cover. The garicus (Fabricius, 1792) (Coleoptera: Carabidae) inhabits answers are highly important for delimitation of conserva- dry calcareous, loess, and sand grasslands from lowlands tion areas, or for deciding between reintroduction and rely- up to nearly 600 m a.s.l. in the Carpathian Basin (Hůrka, 1996; Bérces et al., 2008). The species is globally declin- * Deceased. 663 ing, protected and/or red-listed in most countries of occur- rence, listed also in Annexes II and IV of the EU Habitats Directive (e.g. Szél et al., 2006; Bérces et al., 2008). As a typical steppe species, the ground beetle Carabus hungari- cus represents Pannonian steppe invertebrates (e.g. Cizek et al., 2012) in EU legislation. Despite previous investiga- tions, no information on mobility of this species has been published. In this paper, we investigate mobility patterns in three populations of the flightless, protected grassland specialist ground beetle, Carabus hungaricus (Coleoptera: Carabi- dae). We applied the power law function to obtain move- ment parameters. We will discuss how the sampling design may affect these estimates based on power law function. The variability in those estimates provides an interesting Fig. 1. Pattern of the distributions of the pitfall traps used in illustration of reliability and comparability of the MMR the three areas in the Czech Republic and Hungary where the based dispersal estimates in ground beetles. dispersal of the ground beetle, Carabus hungaricus (Coleoptera: MATERIAL AND METHODS Carabidae), was studied using mark-recapture. Sampling sites and sampling design pling focused on grasslands and took place from 2.9.–19.10.2008. The beetles were sampled at three locations (Fig. 1), includ- (Table 1). ing (i) Pouzdrany steppe, and (ii) Tabulova in southern Mora- ad (iii), the locality is an island in the Danube River with three via (Czech Republic), and (iii) szentendre island near Budapest sand dune areas, all belonging to the authority of the Duna-Ipoly (Hungary). at each site, beetles were individually marked by National Park. It is a site of Community Importance with the ap- numbers or codes engraved on their elytra; after marking, they pellation of “HUDI20047 szigeti homokok”. area near the vil- were released immediately. lage of Pócsmegyer (about 170 ha, 100–120 m a.s.l.) comprising ad (i), the locality is protected as National Nature Reserve and 40 ha is covered with tall-grass vegetation of the Pannonian sand site of Community Importance (total area: 180.8 ha, 200–300 m steppes (Festucetum vaginatae) and was selected as the study a.s.l.), with C. hungaricus as one of its target species. It repre- site. These grasslands are fragmented by patches of black locust sents one of the largest remnants of subcontinental steppic grass- plantations (Robinia pseudoacacia). 270 non-baited pitfall traps lands in the region. It is partly overgrown with shrubs and trees were placed in a 4 × 4 m grid in 10 rows and 27 columns, covering due to abandonment and hands-off conservation approach. Ac- an area of 0.4 ha. sampling focused on grasslands and took place tive management, consisting of grazing and mowing, was partly from 9.5.–28.10.2008. see Table 1 and Bérces & Elek (2013) for reestablished after 1989. 204 live-capture pitfall traps were po- details. sitioned across the steppe and its vicinity, distributed at various Data analysis distances. The minimum distance between neighbouring traps For dispersal analyses, straight distances between capture was 5 m. Sampling focused on grasslands, but covered a wide points (traps) were summed to obtain the movements for each range of habitats and vegetation types. sampling took place from beetle recaptured at least once. Based on these distances, we 26.3.–6.11.2006. see Table 1 and Pokluda et al. (2012) for details. computed for each sex and site the inverse power function (IPF), ad (ii), the locality is part of Pálava Protected landscape area, expressing the probability density I of movements to distances D: and stolová hora site of Community Importance (total area: 77.1 ha, 380–450 m a.s.l.), covered by remnants of subcontinental, I ~ C × Dn calcareous steppic grasslands on limestone. 100 live-capture pit- The function is fitted by plotting the logarithm of cumulative fall traps were positioned across steppe at various distances. The fractions of individuals moving specific or greater distances (lnI) minimum distance between neighbouring traps was 5 m. Sam- against linearized expressions of the distances, i.e., lnI = lnC – n(lnD) (Hill et al., 1996; Fric & Konvicka, 2007). Parameter n, TABLE 1. Basic information on the sampling